1. Field of the Invention
This invention relates generally to an apparatus for displaying a data stored in a memory on a display panel, such as a cathode ray tube and more particularly is directed to such apparatus with a controller for controlling the scroll speed of the data to be displayed and scrolled on a display panel.
2. Description of the Prior Art
In an editing machine for editing signals reproduced from video tape recorders, an automatic editing operation in which the data, such as the number of the tape in which a desired scene is recorded, starting and ending time codes of the desired scene and the way of how to connect the scenes, that is, cut, wipe or dissolve is stored in a memory in sequence according to the sequence of the editing and the stored data in the memory is utilized for editing is proposed. In such a automatic editing operation, there is an requirement to check the data by which the editing is finished in the course of editing. In an existing machine, the data stored in the memory is retrieved sequentially and supplied to a printer and the data is printed out on the paper. However, according to this method, a large amount of paper for printing out is required and the control of the printed out paper is very troublesome. Therefore, another method in which the retrieved data is converted to a video signal and is supplied to a monitor receiver is proposed. And, in this case, the data is displayed in a scroll mode. According to this scroll mode, each time the data of one column is read out from the memory the display on the screen is shifted up by one column and the newly read out data is displayed at the bottom column, thereby the contents of display are run upward. However in this method, the scroll speed of the display is constant or is changeable in two or three steps, and the speed can not be varied linearly. Therefore when the scroll speed is selected to be slow, a long time is required to find out the desired data and when the scroll speed is selected to be fast, it is difficult to stop scrolling at a desired position. Further, various kinds of operation keys, such as a scroll key, a speed change key, and a scroll stop key are required and so the operation is very complicated.